Abstract

Accelerating threats to biodiversity increases the number of species requiring listing status judgments under the United States Endangered Species Act. Understanding that complex environments allow for heuristics to influence (and perhaps bias) cognitive decision processes, we hypothesized that scientific expert judgments may be biased when dealing with decisions under uncertainty. More specifically, we surveyed scientists (n=593) to examine how belonging to different social groups may be associated with the scientists’ perceived norms amongst peers, their personal wildlife value orientations, and ultimately, listing status judgments for the Greater Yellowstone Ecosystem population of grizzly bears (Ursus arctos horribilis). Overall, a majority (74%) of scientists recommended continued Endangered Species Act protections for Greater Yellowstone Ecosystem grizzly bears. Scientists’ professional affiliation (government agency vs. academia) was strongly associated with listing status recommendations; agency experts were 7.3 times more likely to recommend delisting grizzlies. Additionally, identifying strongly as “hunter” or “animal rights advocate” and membership in certain professional societies (e.g., The Wildlife Society) were significantly related to listing status judgments, wildlife value orientations, and expert norms. These results indicate that expert judgment regarding imperiled species may not always be determined solely by the best scientific data available. The simplest way to counteract these potential biases in conservation decision-making is to ensure scientific experts are (a) aware that such social and professional biases exist, and (b) construct groups with decision-making authority so that they have a more heterogeneous composition.